Field
The disclosed concept pertains generally to switchgear systems. The disclosed concept further pertains to electrical switching apparatus assemblies for switchgear systems such as, for example, electrical switching apparatus assemblies including circuit breakers. The disclosed concept further pertains to methods of maintaining electrical switching apparatus assemblies within switchgear systems.
Background Information
Electrical switching apparatus used in power distribution systems are often mounted within a switchgear enclosure either individually or in combination with other switchgear (e.g., without limitation, circuit switching devices and circuit interrupters such as circuit breakers, contactors, motor starters, motor controllers and other load controllers). Some electrical switching apparatus such as, for example, some medium-voltage and low-voltage circuit breakers, can be relatively large. In order to facilitate movement (e.g., installation; removal; maintenance), some circuit breakers are commonly coupled to draw-out mechanisms which permit such circuit breakers to be drawn out of a corresponding compartment or cell of the switchgear enclosure. Accordingly, such circuit breakers are commonly known in the art as “draw-out” circuit breakers.
Arc fault events in switchgear systems, which can result from a number of causes, such as, for example, bad or worn material, voltage spikes, and/or entry into the switchgear system by an animal (e.g., a rodent), produce high energy gases, which pose a threat to the structure and nearby personnel. During an arc fault event inside of the switchgear system, the electrical arc generates a spike in the heat and pressure within the switchgear compartment. The amount of pressure generated during the arc fault is directly related to the length of the arc. Maintaining the position of the circuit breaker with respect to the circuit bus stabs of the switchgear system is key to minimizing the length of the electrical arc. Furthermore, if the pressure from the electrical arc pushes the circuit breaker off of the circuit stabs, additional arcing develops, further increasing the pressure within the switchgear system and resulting in more potentially hazardous damage. This increased pressure creates a potential for the circuit breaker to be undesirably ejected from the switchgear enclosure compartment.
There is, therefore, room for improvement in switchgear systems and in electrical switching apparatus assemblies therefor.
There is also room for improvement in methods of maintaining electrical switching apparatus assemblies in switchgear systems.